That's why I explained it.

https://bitcointalk.org/index.php?topic=1443867.0

Can't make it any clearer (unless cognitive dissonance, or worse, is the real problem).

BTW, masternodes compound the problem of mining centralization, so stating a problem to explain the need for a new problem is not what you are doing here (though it's still weird logic) you are actually adding another problem that is most likely worse--and, in dash's case, is worse.

Also, I don't watch markets that much, but is there a corollary between masternodes and stable price? Both XMR and dash seem to have similar price fluctuations. If that's true, then your original argument goes out the window (masternodes=price stability). Aren't there already benefits to miners and services running full-nodes? If so, then increased mining and services should correspond with node increase.

Although even the incentivized node as price stabilizer isn't really a valid argument in itself. Unless you account for the coins being removed from the market, you aren't really saying nodes are creating the upward or stabilizing pressure--you could very turn the argument to, "Why doesn't dash have a CryptoKingdom style game to stabilize the price?"